Arts related to optical imaging systems include, for example, the one described in Japanese Unexamined Patent Application Publication No. 11-148897. As one type of optical imaging system, an optical imaging system referred to as an optical coherence tomography system is known. The optical coherence tomography system has an optical probe that is inserted into a human body and that has a light receiving/emitting means incorporated in the distal part thereof. The light receiving/emitting means emits low coherence light beam to an object through a light receiving/emitting port and receives light reflected from the object. Based on the reflected light the optical probe receives from the object, a tomographic image of the object is produced by utilizing the interference of light.
In the optical imaging system, an optical scanner probe is connected to a main body of an observing device through a connector by which the optical scanner probe can be freely detachably attached to the main body. The probe can be readily replaced with another.
Aside from the above optical imaging system, for example, Japanese Patent Application No. 11-134590 has disclosed another type of optical imaging system. This type of optical imaging system includes a rotational driving means, which rotates an optical scanner probe, and an advancement/withdrawal driving means, which advances or withdraws the optical scanner program in axial directions, so as to produce a three-dimensional tomographic image of an object.
In the optical imaging system described in the Japanese Unexamined Patent Application Publication No. 11-148897, when a plurality of types of optical probes that are different from one another in terms of a scanning range within which an optical probe can scan data, a focal length, or the diameter of a sheath are used, a human being by himself/herself must discriminate one type of optical probe from the others. The human being then has to carry out time-consuming work, that is, manually determine the settings of the system (hardware and software alike) based on the type of optical probe and the characteristics thereof.
Moreover, in the related art, no consideration is taken into a change in any parameter (for example, the diameter of a probe or a focal point) other than a difference in the length of an optical scanner probe. Therefore, optical scanner probes that are different from one another in terms of any parameter other than the length thereof (different types of optical scanner probes) are not interchangeable.
Furthermore, in the related art, a human being must discern a difference in the lengths of optical scanner probes. An optical path length is manually adjusted in order to correct the length. Detection, discernment, and adjustment are time-consuming.
On the other hand, the optical imaging system described in the Japanese Patent Application No. 11-134590 is a dedicated three-dimensional optical imaging system. The optical imaging system is therefore of little general-purpose. When an optical scanner probe other than a three-dimensional optical scanner probe is used in combination, it is hard to control the system and display images suitable to the probe therewith. Thus, the optical imaging system has low adaptability.
Moreover, in the above system, it is hard to find a focal point at which a resolution of a displayed tomographic image is the highest. An operator has to find a focal point with his/her eyes. It therefore takes too much time to achieve diagnosis. In particular, when a plurality of types of optical probes are employed, since the focal points of the optical probes are different from one another, it is very hard to find where is the focal point of an optical probe.
Furthermore, the conventional optical imaging systems have not taken measures to obviate the necessity of correcting an individual difference of an optical probe that is freely detachably attached to a main body.
Furthermore, the conventional optical imaging systems include a scanning means that includes a scanner but do not attempt to control an image producing means using information, which is acquired by the scanning means, in consideration of the characteristics of an optical probe.
Moreover, in the conventional optical imaging systems, a gain to be produced is controlled based on the property of return light from an object to be observed which is measured in advance. It is therefore necessary to measure the property of return light relative to each probe whose optical characteristics are different from the others. Gain control is therefore labor-intensive.
Furthermore, in the conventional optical imaging systems, bandwidth is optimally adjusted by observing an object to be observed and by manually adjusting a bandwidth limitation filter. Every time a probe whose optical characteristics are different from a reference probe, or every time an object is observed using the same probe, the bandwidth must be regulated. This is bothering.
Moreover, in the conventional optical imaging systems, a predetermined gamma is calculated in advance relative to an object to be observed. An actual gamma is corrected based on the calculated value. It is therefore necessary to acquire and adjust the gamma every time an optical probe whose optical characteristics are different from a reference probe. Attending to gamma control is labor-intensive. The conventional optical imaging systems include, for example, like the system described in Japanese Unexamined Patent Application Publication No. 2000-75210, an optical imaging system having two scanners driven to scan inputs while tracing a Lissajous figure. However, the optical imaging system described in the Japanese Unexamined Patent Application Publication No. 2000-75210 does not provide measures against the conditions for driving the scanners, the details of an operating procedure, and imaging.
The present invention attempts to address the foregoing situations. An object of the present invention is to provide an optical imaging system and an optical imaging detection method capable of automatically detecting and identifying the characteristics of any of a plurality of types of optical probes.
Another object of the present invention is to provide an optical imaging system that automatically detects the characteristics of an optical probe (including a scanning technique, a focal point, and the diameter of a sheath) so a to control the probe optimally relative to the type thereof or determine an optimal display. Otherwise, the optical imaging system presents on a display image the information of the type of optical probe or of the characteristics thereof or enables designation of the information thereof.
Still another object of the present invention is to provide an optical imaging system capable of scanning-drive controlling, a light path adjusting, or a display image adjusting, suitable to a connected optical probe.